It can be perplexing for students to begin counting at 0 when they enter a CS class. I made it a point over and over to talk about "Day 0" and "Week 0" in the opening days and weeks just to build familiarity with the idea. Even so, I sought when explaining this idea to ground it in some real-life/non-CS example where we as humans use 0-indexing naturally and possibly without knowing it.
Question: where can we find 0-indexing outside of CS and grounded in everyday human experience?
I'll share the one example I can think of below (Q&A style), but I'd love to hear more, potentially better, examples.
[Note: This question relates to another I just posed.]